|  | #!/usr/bin/env python | 
|  | #===----------------------------------------------------------------------===## | 
|  | # | 
|  | #                     The LLVM Compiler Infrastructure | 
|  | # | 
|  | # This file is dual licensed under the MIT and the University of Illinois Open | 
|  | # Source Licenses. See LICENSE.TXT for details. | 
|  | # | 
|  | #===----------------------------------------------------------------------===## | 
|  |  | 
|  | from argparse import ArgumentParser | 
|  | import sys | 
|  |  | 
|  | def print_and_exit(msg): | 
|  | sys.stderr.write(msg + '\n') | 
|  | sys.exit(1) | 
|  |  | 
|  | def main(): | 
|  | parser = ArgumentParser( | 
|  | description="Concatenate two files into a single file") | 
|  | parser.add_argument( | 
|  | '-o', '--output', dest='output', required=True, | 
|  | help='The output file. stdout is used if not given', | 
|  | type=str, action='store') | 
|  | parser.add_argument( | 
|  | 'files', metavar='files',  nargs='+', | 
|  | help='The files to concatenate') | 
|  |  | 
|  | args = parser.parse_args() | 
|  |  | 
|  | if len(args.files) < 2: | 
|  | print_and_exit('fewer than 2 inputs provided') | 
|  | data = '' | 
|  | for filename in args.files: | 
|  | with open(filename, 'r') as f: | 
|  | data += f.read() | 
|  | if len(data) != 0 and data[-1] != '\n': | 
|  | data += '\n' | 
|  | assert len(data) > 0 and "cannot cat empty files" | 
|  | with open(args.output, 'w') as f: | 
|  | f.write(data) | 
|  |  | 
|  |  | 
|  | if __name__ == '__main__': | 
|  | main() | 
|  | sys.exit(0) |